An aircraft includes various hierarchically related sub-systems such as, propulsion systems, flight management systems, etc., that communicate over one or more networks. Legacy aircraft contain a defined set of systems and needed wiring to support the systems. In order to add functionality to a legacy aircraft, the system can be modified to add the functionality, or a new system can be added or provided in place of the existing system to add the functionality. For example, to add a new performance application, the flight management system (FMS) software must be modified. To add the display of the newly computed value on a displayed map, both the FMS software and display software must be modified. In another example, the new performance application could be added to a new system that would require an update to the wiring. Either option can be costly and or time consuming to add the new performance application.
Hence, there is a need for improved methods and for integrating new applications in a legacy aircraft. In addition, there is a need for improved methods and systems for accessing data in any system. Other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.